IBM DS8800, Introduction And Planning Manual, Page: 80 / 256

Change recording
Activates the change recording function on the volume pair that is
participating in a FlashCopy relationship. This enables a subsequent refresh
to the target volume.
Establish FlashCopy on existing Metro Mirror source
Allows you to establish a FlashCopy relationship where the target volume
is also the source of an existing remote mirror and copy source volume.
This enables you to create full or incremental point-in-time copies at a local
site and then use remote mirroring commands to copy the data to the
remote site.
Fast reverse
Reverses the FlashCopy relationship without waiting for the finish of the
background copy of the previous FlashCopy. This option applies to the
Global Mirror mode.
Inhibit writes to target
Ensures that write operations are inhibited on the target volume until a
refresh FlashCopy operation is complete.
Multiple Relationship FlashCopy
Allows a source volume to have multiple (up to 12) target volumes at the
same time.
Persistent FlashCopy
Allows the FlashCopy relationship to remain even after the FlashCopy
operation completes. You must explicitly delete the relationship.
Refresh target volume
Provides the ability to refresh a FlashCopy relationship, without recopying
all tracks from the source volume to the target volume.
Resynchronizing FlashCopy volume pairs
Provides the ability to update an initial point-in-time copy of a source
volume without having to recopy your entire volume.
Reverse restore
Reverses the FlashCopy relationship and copies data from the target
volume to the source volume.
Remote Pair FlashCopy
Figure 14 on page 59 illustrates how Remote Pair FlashCopy works. If
Remote Pair FlashCopy is used to copy data from Local A to Local B, an
equivalent operation is also performed from Remote A to Remote B.
FlashCopy can be performed as described for a Full Volume FlashCopy,
Incremental FlashCopy, and Dataset Level FlashCopy.
The Remote Pair FlashCopy function prevents the Metro Mirror
relationship from changing states and the resulting momentary period
where Remote A is out of synchronization with Remote B. This feature
provides a solution for data replication, data migration, remote copy, and
disaster recovery tasks.
Without Remote Pair FlashCopy, when you established a FlashCopy
relationship from Local A to Local B, using a Metro Mirror primary volume
as the target of that FlashCopy relationship, the corresponding Metro
Mirror volume pair went from "full duplex" state to "duplex pending" state
as long as the FlashCopy data was being transferred to the Local B. The
time it took to complete the copy of the FlashCopy data, until all Metro
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Introduction and Planning Guide